Remove bandit tox environment
Remove bandit tox environment

bandit is now part of linters environment, remove it from tox.ini.

Depends-On: I67ebec070cd0804d310534712a3a3f382df7e48f
Change-Id: Ie59ee56f15a857926eef4a7b466637686e116b07

klmitch/python-keystoneclient,klmitch/python-keystoneclient